The present invention relates to compositions for dyeing keratinic fibers, which contain p-phenylene-diamine derivative substituted by an imidazolyl group, the use of these compounds for dyeing keratinic fibers, a process for dyeing fibers using these compounds, and some of these p-phenylenediamine derivatives per se.
For dyeing keratinic fibers, in particular human hair, “oxidation dyes”, because of their intense color and good fastness properties, play a preferred role. Such colorants contain oxidation dye precursors, “developer components” and “coupler components”. Under the influence of oxidants or of atmospheric oxygen, the developer components form the actual dyes mutually or by coupling with one or more coupler components.
The developer components employed are customarily primary aromatic amines having a further free or substituted hydroxy or amino group situated in the para- or ortho-position, diaminopyridine derivatives, heterocyclic hydrazones, 4-aminopyrazolone derivatives and 2,4,5,6-tetraaminopyrimidine and its derivatives.
Specific representatives are, for example, p-phenylene-diamine, p-toluylenediamine, 2,4,5,6-tetraamino-pyrimidine, p-aminophenol, N,N-bis(2′-hydroxyethyl)-p-phenylenediamine, 2-(2′,5′-diaminophenyl)ethanol, 2-(2′,5′-diaminophenoxy)ethanol, 1-phenyl-3-carboxy-amido-4-aminopyrazol-5-one, 4-amino-3-methylphenol, 2-aminomethyl-4-aminophenol, 2-hydroxy-4,5,6-triamino-pyrimidine, 2,4-dihydroxy-5,6-diaminopyrimidine, 2,5,6-triamino-4-hydroxypyrimidine and 1,3-N,N′-bis(2′-hydroxyethyl)-N,N′-bis(4′-aminophenyl)diaminopropan-2-ol.
The coupler components used are, as a rule, m-phenylenediamine derivatives, naphthols, resorcinol and resorcinol derivatives, pyrazolones and m-amino-phenols. Suitable coupler substances are, in particular, 1-naphthol, 1,5-, 2,7- and 1,7-dihydroxy-naphthalene, 5-amino-2-methylphenol, m-aminophenol, resorcinol, resorcinol monomethyl ether, m-phenylene-diamine, 1-phenyl-3-methylpyrazol-5-one, 2,4-dichloro-3-aminophenol, 1,3-bis(2,4-diaminophenoxy)propane, 2-chlororesorcinol, 4-chlororesorcinol, 2-chloro-6-methyl-3-aminophenol, 2-methylresorcinol, 5-methyl-resorcinol and 2-methyl-4-chloro-5-aminophenol.
Good oxidation dye precursors should primarily fulfill the following requirements: they must form the desired color shades in adequate intensity and fastness on oxidative coupling. They must further possess a good absorptive power to the fibers, where in particular in the case of human hair no noticeable differences must exist between damaged hair and freshly rewashed hair (leveling power). They should be resistant to light, heat, perspiration, friction and the influence of chemical reductants, e.g. permanent waving liquids. Finally, they should—if being used as hair dyes—not dye the scalp too much, and, especially, they should be harmless toxicologically and dermatologically. Furthermore, the dyeing obtained should be able to be removed easily from the hair again by bleaching if it does not conform to the individual wishes of the particular person and is to be reversed.
Using a developer component or a specific coupler/developer combination on its own, as a rule it is not possible to obtain a color shade acting naturally on the hair. In practice, combinations of various developer and/or coupler components are therefore customarily employed. There is therefore continually a need for novel, improved dye components, which are also nonproblematical toxicologically and dermatologically.
It was therefore an object of the present invention to develop novel developer components which fulfill the requirements placed on oxidation dye precursors and make possible dyeings in a wide color spectrum having good fastness properties.
Surprisingly, it has now been found that specific imidazole-substituted p-phenylenediamine derivatives meet the requirements placed on oxidation dye precursors to a high extent. The developer components according to the invention are distinguished by intense color results with excellent perspiration fastness and cold wave fastness. The color loss of dyeings in combination with conventional dye precursors is shifted somewhat to bluish compared with the dyeings using p-toluylenediamine.